Not All Patients with a Headache need a CT Scan, but they should be Listened to, and also with a Stethoscope: A Report of a Large Arteriovenous Malformation with a Loud Cranial Bruit.

Background: Arteriovenous malformations (AVMs) are abnormal direct connections between arterial and venous systems, without an interposed capillary bed. This permits high-flow arteriovenous shunting, which precipitates structural changes in the afferent and efferent vessels, namely arterial smooth muscle hyperplasia and thinning of venous walls. Patients with intracranial AVMs typically present with a haemorrhage, headache or seizure. Treatment is either via medical management aimed at control of seizures, headache and blood pressure, or interventional via surgical, radiation or radiologically guided embolisation. Case description: We report the case of a woman in her early 40s presenting with a tonic-clonic seizure against a background of a 31-year history of migraine and an 18-month history of tremors in her right arm. The clinical examination was remarkable for an extremely loud cranial bruit and a right homonymous hemianopia. Imaging diagnosed an 8 cm Martin-Spetzler grade V intracranial arteriovenous malformation in her left parietal lobe, which was deemed unsuitable for operative or radiotherapy-based intervention. Conclusion: The patient was managed through observation and relatively good control of her breakthrough seizures was achieved through the addition of brivaracetam to her lamotrigine and carbamazepine-based therapy, six years after her initial presentation. LEARNING POINTS: Arteriovenous malformations may go undetected for decades.The presence of a cranial bruit is an important sign and tool in diagnosing an intracranial arteriovenous malformation. The presence of a homonymous hemianopia, of which a patient may be unaware, helps to localise an intracranial lesion.The risks of operative or radiological intervention must be balanced with the risks of haemorrhage or refractory seizure when adopting a strategy for the treatment of an intracranial arteriovenous malformation. Good control of epileptic symptoms in those deemed not suitable for operative or radiological intervention can be achieved by careful titration of anti-seizure medications.

The Challenge of Strabismus Surgery for Patients with Hemianopic Visual Field Defects Associated with Ocular Deviations.

Homonymous and heteronymous hemianopias associated with strabismus are a therapeutic challenge because surgery may result in diplopia, decrease the visual field (VF), and/or lead to recurrence of the deviation. We present four cases: two homonymous hemianopias and two heteronymous hemianopias. Of the four patients, three had exotropia and one had esotropia. The origin of hemianopias was neoplastic in two cases and traumatic in two cases. Strabismus surgery was performed in three cases, but only one case had a good result; recurrence of the deviation and diplopia occurred in the other two cases. In conclusion, exotropia may develop as a compensatory mechanism in a patient with congenital or early-onset homonymous hemianopia and realigning the eyes could reduce the binocular VF and cause diplopia. In heteronymous hemianopias, there is little risk of the surgery causing diplopia, but the strabismus is unstable because of the absence of binocular vision and vergence reflexes if VF loss includes the macula. Further, strabismus, in association with hemianopia, may be caused by coexistent cranial nerve and/or gaze palsy. The prognosis, objective, and results of the strabismus operation should be clearly discussed with the patients or their guardians before it is performed if hemianopias are present.

Idiopathic Intracranial Hypertension Preceding Tumefactive Multiple Sclerosis.

Idiopathic intracranial hypertension (IIH) and multiple sclerosis (MS) are rare neurological disorders that largely affect females within the reproductive age group. The clinical pictures of both diseases can overlap, which therefore places great importance on accurately studying and reporting their concurrence. Therein, we report a case of IIH presenting and progressing simultaneously with MS. This young, previously healthy female presented with the primary complaint of a severe right-sided headache associated with blurred vision and a finding of papilledema. The initial investigations including a lumbar puncture (LP) that revealed high opening pressure (more than 25 mm H2O) with normal cerebrospinal fluid (CSF) analysis led to an impression of idiopathic intracranial hypertension, and she was treated accordingly with acetazolamide and scheduled for regular follow-ups with both neurology and neuro-ophthalmology. However, about two months after the initial presentation, she complained of unusual headaches, and a neuro-ophthalmology clinical evaluation revealed complete right homonymous hemianopia, suggesting a lesion in the left temporo-parietal occipital region. The patient was thus admitted as a case of cerebral edema following an urgent brain magnetic resonance imaging (MRI). After obtaining thorough imaging and workup, the patient was given steroids and markedly improved, favoring a diagnosis of tumefactive MS with IIH.

Efficacy of Neuro-Optometric visual rehabilitation in Homonymous Hemianopia.

OBJECTIVES: To assess oculomotor dysfunction and the effectiveness of neuro-optometric visual rehabilitation in improving oculomotor parameters in participants with homonymous hemianopia. MATERIALS AND METHODS: Fifty subjects diagnosed with homonymous hemianopia (HH), referred through the neuro-ophthalmology department, were recruited for the study. All the subjects underwent a detailed neuro-optometric evaluation that included testing for sensory, visuo-motor and oculomotor functions. Subjects with homonymous hemianopia were then prescribed with yoked prisms and were randomized to two treatments at one month, namely group 1: yoked prisms (n = 15) and group 2: yoked prisms with in-office visual search training (n = 15). RESULTS: The mean ± SD age of the subjects was 46 ± 12 years. Subjects with HH exhibited a significant delay in the completion time, response and accuracy of tasks on proactive, saccadic and visual search parameters using the SVI compared to age-matched controls (Independent t-test, p < 0.05). A significant improvement in the reading speed and visual search parameters (RM ANOVA, p < 0.001) was seen post neuro-optometric visual rehabilitation with both yoked prisms and SVI. Statistically significant differences were observed in the reaction time of the visual search paradigms between the two rehabilitative modalities yoked (group1), yoked and SVI (group2) (Mann-Whitney U test, p < 0.001), with the group 2 showing better visual search performance outcomes compared to group 1 (yoked). CONCLUSION: Visual search parameters among participants with homonymous hemianopia improved following combined rehabilitation (yoked prisms and visual search trainng).

FunctionaL Assessment Scale of Hemianopia (FLASH): A New Multidisciplinary Tool to Assess Hemianopia in Patients with Severe Acquired Brain Injury.

BACKGROUND: Severe acquired brain injury (sABI) encompasses a range of neurological impairments. Visual dysfunction, particularly homonymous visual field defects (HVFDs) and homonymous hemianopia (HH), commonly afflicts sABI survivors, affecting their cognitive and motor rehabilitation. This study presents the FunctionaL Assessment Scale of Hemianopia (FLASH), developed to analyze the most common postural behaviors exhibited by sABI patients with hemianopia during activities of daily living. A comparison to traditional static automated perimetry for diagnosing visual field deficits (VFDs) to determine the sensitivity and specificity of the FLASH was used. Additionally, this study also aimed to assess its reliability. METHODS: Fifty-six patients (25 F, 31 M, mean age 60.59 ± 14.53) with strokes in the sub-acute phase (<6 months from the onset) were assessed with both FLASH and a Humphrey Field Analyzer. RESULTS: After removing two items found to be less reliable than others, FLASH showed high sensitivity (81%) and specificity (77%) when compared to static automated perimetry. Inter-rater reliability was also high, with an intra-class correlation coefficient of 0.954, as well as the internal consistency computed by Cronbach's alpha, equal to 0.874. CONCLUSION: FLASH could offer a valuable and cost-effective screening tool for VFD in sABI patients during neurorehabilitation, with potential implications for healthcare cost reduction.

Case report: Findings of automated perimetry during a migraine episode in a patient with glaucoma.

Comorbidities like glaucoma and migraine are often observed among middle-aged individuals, especially women. Herein, we report a rare case of a patient who underwent automated perimetry during a migraine attack. A 52-year-old woman with a 1-year history of blurred vision in the nasal field of her right eye visited Miyoshi Eye Clinic. The intraocular pressures of the right and left eyes were 22 and 24 mm Hg, respectively. Retinal imaging revealed a retinal nerve fiber defect in the temporal superior macula with corresponding thinning of the superior ganglion cell complex in the right eye. The left eye appeared normal. Primary open-angle glaucoma was suspected, and the patient underwent a visual field examination on the same day. Perimetry showed that the mean deviations in the right and left eyes were -5.00 and -7.68 dB, respectively. A visual field defect in the inferior nasal aspect of the right eye corresponded to the retinal nerve fiber defect. However, right-sided homonymous hemianopia-like visual field defects were observed in both eyes. After the examination, the patient stated that a migraine attack had started 5 min before the examination and continued till after its end (attack duration was ∼20 min). In the follow-up examinations without migraine, homonymous hemianopia-like visual field defects disappeared, and only a glaucomatous visual field defect in the right eye was observed. Hence, the initial visual field examination findings reflected the effects of a migraine attack alongside glaucoma. Detailed interviews with patients may be beneficial for understanding visual field findings and preventing their untimely examination.

Occipital Seizures and Persistent Homonymous Hemianopia (HH) With MRI Subcortical T2 Hypointensity in a Newly Diagnosed Diabetic Patient.

Non-ketotic hyperglycemia (NKH) can often cause seizures. Although these are usually in the form of focal seizures, occipital seizures have also been reported in case reports. Patients may present with complaints ranging from blurred vision and bright lights to homonymous hemianopia (HH) in occipital seizures due to hyperglycemia. Seizures can often be brought under control in a short time with good glycemic control. Seizures associated with NKH may cause subcortical T2 hypointensity on MRI in the occipital lobes and occipital epileptiform discharges on the electroencephalogram. In this case study, we aim to present a newly diagnosed diabetes mellitus patient who had homonymous hemianopsia in his neurological examination, had imaging and electrophysiological findings consistent with his examination and clinical findings, was admitted 15 days after his symptoms started, and whose seizures could not be controlled by glucose regulation. In this context, we evaluated the literature and compared our case to other patients who required anti-seizure drugs, with the goal of emphasizing the need of early treatment in seizures caused by NKH.

The nature of blindsight: implications for current theories of consciousness.

Blindsight regroups the different manifestations of preserved discriminatory visual capacities following the damage to the primary visual cortex. Blindsight types differentially impact objective and subjective perception, patients can report having no visual awareness whilst their behaviour suggests visual processing still occurs at some cortical level. This phenomenon hence presents a unique opportunity to study consciousness and perceptual consciousness, and for this reason, it has had an historical importance for the development of this field of research. From these studies, two main opposing models of the underlying mechanisms have been established: (a) blindsight is perception without consciousness or (b) blindsight is in fact degraded vision, two views that mirror more general theoretical options about whether unconscious cognition truly exists or whether it is only a degraded form of conscious processing. In this article, we want to re-examine this debate in the light of recent advances in the characterization of blindsight and associated phenomena. We first provide an in-depth definition of blindsight and its subtypes, mainly blindsight type I, blindsight type II and the more recently described blindsense. We emphasize the necessity of sensitive and robust methodology to uncover the dissociations between perception and awareness that can be observed in brain-damaged patients with visual field defects at different cognitive levels. We discuss these different profiles of dissociation in the light of both contending models. We propose that the different types of dissociations reveal a pattern of relationship between perception, awareness and metacognition that is actually richer than what is proposed by either of the existing models. Finally, we consider this in the framework of current theories of consciousness and touch on the implications the findings of blindsight have on these.

Transcranial direct current stimulation with multiple oral re-reading therapy for pure alexia without agraphia: a case report.

Pure alexia without agraphia is characterized by impaired reading due to damage to the occipitotemporal cortex with preserved writing skills. In this case report, we investigate the effect of multiple oral re-reading (MOR) therapy adjunct with transcranial direct current stimulation (tDCS) in improving reading recovery of a 64-year-old patient with pure alexia without agraphia following a stroke. His MRI revealed an area of infarct with microhemorrhages at the left occipitotemporal region. The patient was blinded to each therapy and underwent seven consecutive sessions of sham tDCS followed by seven consecutive sessions of real tDCS, coupled with 1-hour MOR therapy during each session. Western Aphasia Battery (WAB) was performed at baseline, before sham and real-tDCS, and 6 weeks after completing tDCS therapy. The patient showed improvement using both sham and real-tDCS with better reading comprehension, average reading time, and word per minute after real-tDCS. This study suggests that MOR, coupled with tDCS therapy may accelerate the reading recovery in patients with pure alexia.

Non-invasive electrical brain stimulation for vision restoration after stroke: An exploratory randomized trial (REVIS).

BACKGROUND: Occipital strokes often cause permanent homonymous hemianopia leading to significant disability. In previous studies, non-invasive electrical brain stimulation (NIBS) has improved vision after optic nerve damage and in combination with training after stroke. OBJECTIVE: We explored different NIBS modalities for rehabilitation of hemianopia after chronic stroke. METHODS: In a randomized, double-blinded, sham-controlled, three-armed trial, altogether 56 patients with homonymous hemianopia were recruited. The three experiments were: i) repetitive transorbital alternating current stimulation (rtACS, n = 8) vs. rtACS with prior cathodal transcranial direct current stimulation over the intact visual cortex (tDCS/rtACS, n = 8) vs. sham (n = 8); ii) rtACS (n = 9) vs. sham (n = 9); and iii) tDCS of the visual cortex (n = 7) vs. sham (n = 7). Visual functions were evaluated before and after the intervention, and after eight weeks follow-up. The primary outcome was change in visual field assessed by high-resolution and standard perimetries. The individual modalities were compared within each experimental arm. RESULTS: Primary outcomes in Experiments 1 and 2 were negative. Only significant between-group change was observed in Experiment 3, where tDCS increased visual field of the contralesional eye compared to sham. tDCS/rtACS improved dynamic vision, reading, and visual field of the contralesional eye, but was not superior to other groups. rtACS alone increased foveal sensitivity, but was otherwise ineffective. All trial-related procedures were tolerated well. CONCLUSIONS: This exploratory trial showed safety but no main effect of NIBS on vision restoration after stroke. However, tDCS and combined tDCS/rtACS induced improvements in visually guided performance that need to be confirmed in larger-sample trials.NCT01418820 (clinicaltrials.gov).

Visual Field Test With Gaze Check Tasks: Application in a Homonymous Hemianopic Patient Unaware of the Visual Defects.

Gaze control is required for applying visual stimuli to a particular area of the visual field. We developed a visual field test with gaze check tasks to investigate hemianopia. In this test, participants must report the presence or absence of visual stimuli when a small object at the fixation point vibrates. Trials in the absence of visual stimuli were used as gaze check tasks, since the vibration could be observed only when the gaze was directed at the fixation point. We evaluated the efficacy of our test in four control participants and one patient with homonymous hemianopia who was unaware of the defects in the left visual field. This patient presented hemianopia in the test with gaze check tasks, but not when the gaze check tasks were omitted. The patient showed spontaneous gaze movements from the fixation point to the upper left direction, as well as scanning of the left visual field during the test without gaze check tasks. Thus, we concluded that the visual defects in this patient were compensated in daily life by spontaneous eye movements coordinated with visual information processing. The present results show the usefulness of the visual field test with gaze check tasks.

Motor Vehicle Accident Due to Homonymous Hemianopia: An Unusual Presentation of Vertebrobasilar Stroke.

Acute ischemic stroke may present with various symptoms, including weakness, altered speech, and sensory and visual impairment. We present a case of a 57-year-old man who was brought to the emergency department after he sustained three minor motor vehicle accidents on the same day. After clinical assessment and detailed workup, we concluded that our patient had an acute ischemic infarct involving the left posterior cerebral artery territories causing right homonymous hemianopia resulting in motor vehicle accidents.

Prognostic Factors for Long-Term Recovery of Homonymous Visual Field Defects After Posterior Circulation Ischemic Stroke.

OBJECTIVES: Ischemic stroke (IS) is the main cause of homonymous visual field defects (HVFDs) in adults. Some reports suggest recovery even in late-phase strokes, but data is sparse. This study examines the frequency of long-term recovery from HVFDs in patients with posterior circulation infarction (POCI) and evaluates whether demographic or clinical characteristics are prognostic factors of perimetric recovery. MATERIALS AND METHODS: Our study included patients with HVFDS due to POCI who had undergone 2 or more kinetic perimetric evaluations at least 6 months after the index IS. Clinical and imaging data were systematically reviewed and we performed univariate and multivariate logistic regression analyses to determine whether demographic, stroke etiology (TOAST classification), and initial perimetric patterns were prognostic factors of visual recovery occurring 6 months and beyond from POCI. RESULTS: One hundred one patients with POCI were included. Median subject age was 60 years and 54.4% were female. After a median perimetric follow-up time of 13.5 months, spontaneous visual improvement was observed in 15.8% of patients. Prognostic factors for visual improvement were age < 50 years (OR 4.6; P = 0.093), POCI associated with hypercoagulable states (OR 12.3; P = 0.048), and vertebral artery dissection (OR 12.6; P = 0.048), while the presence of complete homonymous hemianopia was a negative predictor of recovery (OR 0.2; P = 0.048). CONCLUSION: Partial visual recovery in HVFDs is observed even 6 months and beyond POCI. Age < 50 years and stroke etiology were predictors of recovery.

The Mechanism of Macular Sparing.

Patients with homonymous hemianopia sometimes show preservation of the central visual fields, ranging up to 10°. This phenomenon, known as macular sparing, has sparked perpetual controversy. Two main theories have been offered to explain it. The first theory proposes a dual representation of the macula in each hemisphere. After loss of one occipital lobe, the back-up representation in the remaining occipital lobe is postulated to sustain ipsilateral central vision in the blind hemifield. This theory is supported by studies showing that some midline retinal ganglion cells project to the wrong hemisphere, presumably driving neurons in striate cortex that have ipsilateral receptive fields. However, more recent electrophysiological recordings and neuroimaging studies have cast doubt on this theory by showing only a minuscule ipsilateral field representation in early visual cortical areas. The second theory holds that macular sparing arises because the occipital pole, where the macula is represented, remains perfused after occlusion of the posterior cerebral artery because it receives collateral flow from the middle cerebral artery. An objection to this theory is that it cannot account for reports of macular sparing in patients after loss of an entire occipital lobe. On close scrutiny, such reports turn out to be erroneous, arising from inadequate control of fixation during visual field testing. Patients seem able to detect test stimuli on their blind side within the macula or along the vertical meridian because they make surveillance saccades. A purported treatment for hemianopia, called vision restoration therapy, is based on this error. The dual perfusion theory is supported by anatomical studies showing that the middle cerebral artery perfuses the occipital pole in many individuals.In patients with hemianopia from stroke, neuroimaging shows preservation of the occipital pole when macular sparing is present. The frontier dividing the infarcted territory of the posterior cerebral artery and the preserved territory of the middle cerebral artery is variable, but always falls within the representation of the macula, because the macula is so highly magnified. For physicians, macular sparing was an important neurological sign in acute hemianopia because it signified a posterior cerebral artery occlusion. Modern neuroimaging has supplanted the importance of that clinical sign but at the same time confirmed its validity. For patients, macular sparing remains important because it mitigates the impact of hemianopia and preserves the ability to read fluently.

Blurring of vision with malaise.

We present the case of a 56-year-old female brought to the Emergency Department via routine ambulance transport with complaints of blurred vision and malaise. She was screened by ambulance crew using the facial arm speech time (FAST) tool and a basic top-to-toe assessment as per current routine. The examining practitioner performed a thorough assessment of the patient, revisiting the initial examination findings, and establishing new clinical features of visual field deficit and pan-systolic murmur. The likely diagnosis of septic emboli or stroke with infective endocarditis was identified through the power of rigorous history taking and examination. These were then supported by investigation with blood tests and imaging. This prompted discussion with a tertiary centre and subsequent transfer for further investigation and management. The patient's journey shows that there may indeed be a role for a more comprehensive (but not exhaustive) initial screening from ambulance services in order to help appropriately stream specific patients to hospital in a timelier manner (to meet the thrombolysis window). This case supports the addition of V (visual fields) to the FAST screening tool.

Irreversible Homonymous Hemianopia Associated with Severe Hyperglycemia and Cerebral Hyperperfusion: A Case Report and Literature Review.

A 68-year-old man was admitted to our department because of left incomplete homonymous hemianopia accompanied by hyperglycemia. Both T2-weighted and diffusion-weighted imaging revealed a low signal intensity along the subcortex and high signal intensity along the cortex on the right parietal and occipital lobes. Furthermore, arterial spin labeling and single-photon emission computed tomography showed hyperperfusion at the right parieto-occipital lobe. However, the electroencephalography result was normal. Hyperperfusion improved after controlling the blood glucose levels; nevertheless, homonymous hemianopia remained. We suspect that the irreversible brain damage was attributable to hyperperfusion associated with long-term hyperglycemia.

Hyperglycemic hemianopia: A case report.

BACKGROUND: Nonketotic hyperglycemia (NKH) is characterized by hyperglycemia with little or no ketoacidosis. Diverse neurological symptoms have been described in NKH patients, including choreoathetosis, hemiballismus, seizures, and coma in severe cases. Homonymous hemianopia, with or without occipital seizures, caused by hyperglycemia is less readily recognized. CASE SUMMARY: We describe a 54-year-old man with NKH, who reported seeing round, colored flickering lights with right homonymous hemianopia. Cranial magnetic resonance imaging demonstrated abnormalities in the left occipital lobe, with decreased T2 signal of the white matter, restricted diffusion, and corresponding low signal intensity in the apparent diffusion coefficient map. He responded to rehydration and a low-dose insulin regimen, with improvements of his visual field defect. CONCLUSION: Patients with NKH may present focal neurologic signs. Hyperglycemia should be taken into consideration when making an etiologic diagnosis of homonymous hemianopia.

[A case of adult-onset Sturge-Weber syndrome type III without intracranial calcification, presenting with transient homonymous hemianopia].

Sturge-Weber syndrome (SWS) is a rare neurocutaneous disorder. Almost all cases of SWS are diagnosed in children, but some are diagnosed in adults. We describe a case of isolated leptomeningeal angiomatosis without intracranial calcification. A 33-year-old woman was admitted because of sudden-onset right homonymous hemianopia with headache and nausea. These symptoms disappeared by the next morning. She had no history of seizure or mental retardation. No facial angioma was found on physical examination. Brain CT showed no intracranial calcification or atrophic cortex. The blood and cerebrospinal fluid analyses yielded normal results. The findings in the electroencephalogram were unremarkable. MRI with susceptibility weighting (SWI) revealed dilated transmedullary veins in the left occipital lobe. Contrast-enhanced T1-weighted imaging (CE-T1WI) illustrated abnormal leptomeningeal enhancement in the left occipitoparietal cortex and enhancement and enlargement of the choroid plexus in the left lateral ventricle. Post-gadolinium contrast-enhanced f FLAIR imaging demonstrated more extensive enhancement of the leptomeningeal lesions than did CE-T1WI. The symptoms and the findings on these images were suggestive of a diagnosis of SWS type III. Clinicians should keep in mind that some cases of SWS manifest with only minor symptoms, such as migraine. If SWS is suspected, SWI and contrast-enhanced MRI should be performed.

Aging and the rehabilitation of homonymous hemianopia: The efficacy of compensatory eye-movement training techniques and a five-year follow up.

The specificity and effectiveness of eye-movement training to remedy impaired visual exploration and reading with particular consideration of age and co-morbidity was tested in a group of 97 patients with unilateral homonymous hemianopia using a single subject /n-of-1 design. Two groups received either scanning training followed by reading training, or vice versa. The third group acted as a control group and received non-specific detailed advice, followed by training of scanning and reading. Scanning and reading performance was assessed before and after the waiting period, before and after scanning and reading training, and at short-term (11 weeks on average) and long-term follow-up (5 years on average). Improvements after training were practice-dependent and task-specific. Scanning performance improved by ∼40%, reading by ∼45%, and was paralleled by a reduction of subjective complaints. The advice (=control) condition was without effect. All improvements occurred selectively in the training period, not in treatment-free intervals, and persisted in the short- and long-term follow-up over several years. Age had only a minor, although significant effect on improvement in reading after training; co-morbidity had no significant impact on the outcome of training. In conclusion, visual impairments associated with homonymous hemianopia can be successfully and durably reduced by systematic and specific training of compensatory eye-movement strategies. The improvements in compensation strategies were independent of subjects' age and of co-morbidity.